相关论文: Scalar field potentials for cosmology

We propose a model with a compensating scalar field whose back reaction to the cosmological curvature cancels possible vacuum energy density down to the terms of the order of the time dependent critical energy density. Thus the model…

The nature of dark matter and of dark energy which constitute more than $95\%$ of the energy in the Universe remains a great and unresolved question in cosmology. Cold dark matter can be made of an ultralight scalar field dominated by its…

The new classes of homogeneous cosmological models for the scalar fields are build in the context of Lyra's geometry. The different types of exact solution for the model are obtained by applying two procedures, viz the generating function…

The present study investigates the nature of the field potential via new technique known as reconstruction method for the scalar field potentials. The key point of this technique is the assumption that Hubble parameter is dependent on the…

In the present study, we investigate the interaction between dark energy and dark matter, particularly emphasizing the effects of curvature in the realm of Friedmann-Lemaitre-Robertson-Walker (FLRW) space-time. We examine the system by…

A coupling between a scalar field (representing the dark energy) and dark matter could produce rich phenomena in cosmology. It affects cosmic structure formation mainly through the fifth force, a velocity-dependent force that acts parallel…

Motivated in part by string theory, we consider a modification of the LambdaCDM cosmological model in which the dark matter has a long-range scalar force screened by light particles. Scalar forces can have interesting effects on structure…

In this work it is investigated the evolution of a Universe where a scalar field, non-minimally coupled to space-time curvature, plays the role of quintessence and drives the Universe to a present accelerated expansion. A non-relativistic…

We discuss a generic form of the scalar potential appearing in the geometric scalar theory of gravity. We find the conditions on the potential by considering weak and strong gravity. The modified black hole solutions are obtained for…

We investigate in this paper the cosmological evolution of a dark energy model with two scalar fields where one of the scalar has canonical kinetic energy and another scalar has negative kinetic energy term. For such a system with…

We study the holographic dark energy model in a generalized scalar tensor theory. In a universe filled with cold dark matter and dark energy, the effect of potential of the scalar field is investigated in the equation of state parameter. We…

We study the phase space of the quintom cosmologies for a class of exponential potentials. We combine normal forms expansions and the center manifold theory in order to describe the dynamics near equilibrium sets. Furthermore, we construct…

A nonsingular emergent universe cosmology can be realized by a nonconventional spinor field as first developed in \cite{Cai:2012yf}. We study the mechanisms of generating scale-invariant primordial power spectrum of curvature perturbation…

The revision of the Author's results with respect to possibility of existence of the so-called Euclidian cycles in cosmological evolution of a system of Higgs scalar fields has been performed. The assumption of non-negativity of the…

We investigate the clustering properties of a dynamical dark energy component. In a cosmic mix of a pressureless fluid and a light scalar field, we follow the linear evolution of spherical matter perturbations. We find that the scalar field…

We investigate cosmological models in a recently proposed geometrical theory of gravity, in which the scalar field appears as part of the space-time geometry. We extend the previous theory to include a scalar potential in the action. We…

Scalar fields coupled to dark matter by conformal or disformal transformations give rise to a general class of scalar-tensor theories which leads to a rich phenomenology in a cosmological setting. While this possibility has been studied…

A cosmological approach based on considering a cosmic background with non-zero torsion is shown in order to give an option of explaining a possible phantom evolution, not ruled out according to the current observational data. We revise some…

Motivated by the recent interest in cosmologies arising from energy density modifications to the Friedmann equation, we analyse the scaling behaviour for a broad class of these cosmologies comprised of scalar fields and background…

It has been argued that the small perturbations to the homogeneous and isotropic configurations of a canonical scalar field in an expanding universe do not grow. We show that this is not true in general, and clarify the root of the…